Circuit breaker mechanism



J. A. co?

June 4, 1940.

CIRCUIT BREAKER MECHANISM Fi led .Jan. 18, 1940 INVENTOR 0y. 1 WfiW ATTORNEY .5

Patented June 4, 1940 UNITED STATES CIRCUIT BREAKER. MECHANISM Joseph A. Coy, Cincinnati, Ohio, assignor to The Wadsworth Electric Manufacturing Company,. Covington, Ky., a corporation of Kentucky Application January 18, 1940, Serial No. 314,464

7 Claims.

factured at a low cost and which operates efficiently and effectively.

Another object of the invention is to provide a circuit breaker switch which has a single resilient means for actuating and resetting the various parts of said switch.

A further object of the invention is to provide a means for opening the breaker contacts upon the occurrence of an overload, said means also serving to reset the switch for manual closing of the breaker contacts.

Other objects will be apparent from the following specification and drawing, in which:'

Fig. 1 is a side elevational view of my circuit breaker with the casing removed.

Fig. 2 is an end elevational view of the switch mechanism of the breaker shown in Fig. 1.

Fig. 3 is a cross-sectional view taken on line 3-3 of Fig. 2, the switch being shown in contact engaging position.

.Fig. 4 is a cross-sectional view similar to that -of Fig. 3 showing the switch in an intermediate position.

Fig. 5 is a cross-sectional view similar to that of Fig. 3 showing the switch in contact disengaged position.

My invention comprises a circuit breaker I having a means responsive to current conditions such as a solenoid 8 and the switch mechanism 9 mounted on a non-conductive base 10. The solenoid has two vertical metal plates II and I2 fastened to the base by means of screws l3 and I4, respectively, the lower end of plate l2 being flanged to form with screw I5 a contact for lead wire N3 of the circuit to be protected. This wire is led to an electrical translating device while the other remaining circuit wire of said device is connected with the service circuit in the conventional manner. An extension I! formed on the flange of thewertical plate It overlies the horizontal portion of a U-shaped support I8 of the switch mechanism, screw l3 serving to clamp the horizontal portion of the U-shaped support between the base and the extension H.

The solenoid has a wire coil I9 supported on a conventional core between the vertical plates I! and I2, said core being disposed centrally of said coil and having located therein a plunger 20 connected to a plunger rod 2! resiliently held in a retracted position within the core by means of a spring 22. The upper ends of the vertical 5 supports may be provided with a compound or bi-metallic element 23, one end thereof being rigidly fastened by means of screw 24 to the plate II, whilst the other end freely engages the plate l2. Oneend of the coil is adapted to elecl0 trically Contact the plate I! whilst the other end of the coil is connected to plate l2.

A movable contact 25, preferably U-shaped in cross-section is rotatably mounted between the side members 26 and 21 of the U-shaped support by means of a pin 28, the outer end thereof being adapted to engage or disengage a resilient stationary contact 29. The stationary contact is fastened to the base ID by a screw 30, which is threaded to a plate 3|, and in tightened condition clamps'said resilient member between the base and said plate. The outer endpf the plate is provided with a screw 32 for binding the end of line wire 33 to the plate 3|. The electrical circuit passing through the breaker when the movable contact is in engagement with the stationary contact is as follows: The load wire Ii, screw l5, vertical plate l2,coi1 l9,vertical plate ll, part of the current being shunted about the coil through bi-metallic element 23, extension I], U-shaped support l8, pin 28, movable contact 25, stationary contact 29, plate 3|, and line wire 13.

It will be understood from the foregoing that when a temporary overload occurs in the protected circuit, the bi-metallic element shunted 35 across the coil terminals will be opened, thereby allowing the full current to pass through the solenoid to actuate the plunger against the spring 22. The rod 2| will then engage the switch mechanism as hereinafter set forth. Upon the occurrence of a dangerous overload, the solenoid will be actuated in the above manner without the assistance of the bi-metallic element.

The switch mechanism as shown in Fig. 2, is mounted as a unit between the side members 28 and 21 of the support 18. The movable contact 25 adapted for movement into and out of engagement with the stationary contact, has for its lower limit of motion said stationary contact, while its upper limit of motion is determined by two stops 34 formed on the side members of the support which engage said contact ,when it moves upwardly. A manually operated switch lever 35 is positioned adjacent the top of the support I 8,

and is rotatably mounted on pin 36 held in the adapted to engage and disengage the stationary contact; a manually operated switch lever; a spring connected to the lever and the movable contact at points removed from their axes; a rotatable link associated with the lever; a toggle element connected to the link and fastened to the pivoted contact intermediate its pivot point and the point where the spring engages said contact; and a means responsive to overload conditions in the circuit for actuating the toggle member.

' 6. A circuit breaker comprising in combination; a stationary contact; a pivoted contact adapted to engage and disengage the stationary contact; a manually operated switch lever; a pin on the lever; a spring connected to the lever and the movable contact; a rotatable link having aslot therein for receiving the pin; toggle members pivoted to the movable contact and to the link; a stop formed on one of the toggle members for holding said members in normal, operative position whereby the movable contact is controlled by the lever; means responsive to current conditions in the circuit for collapsing the toggle members to an inoperative position to move the movable contact to disengaged position; and means for automatically returning the toggle to operative position after it has been collapsed.

7. A circuit breaker comprising in combination; a stationary contact; a pivoted contact adapted to engage and disengage the stationary contact; a manually operated switch lever rotatable to and. from predetermined ofl and on positions; a link'and toggle mechanism connected 

